It is one of the two chapels built in the 6th century as part of a large Benedictine abbey demolished in the 16th century. The floor and walls were decorated with mosaics, some of which are now in the Archaeological Museum of Istria. It was built in the style of Ravenna churches, the only difference being the use of stone instead of brick. Due to its dimensions, method of construction and good state of preservation, the Chapel represents an extraordinary architectural masterpiece of its time. https://www.pulainfo.hr/where/chapel-st-maria-formosa